Community low-dose CT lung cancer screening: a prospective cohort study

The National Lung Screening Trial (NLST) in 2011 showed that low-dose CT (LDCT) screening in high-risk groups reduces lung cancer deaths. Major professional organizations, as well as the U.S. Preventative Services Task Force, have endorsed LDCT screening in these select populations. However, major questions remain about whether widespread deployment of CT screening can achieve results similar to the NLST, especially in the community setting.

A prospective cohort study was initiated in November 2010. Participants at least 50 years old and with at least 20 pack-years of smoking history underwent LDCT screening in a community setting.

One hundred and fifty four participants underwent LDCT screening with median follow-up of 2.7 years. Compared with the NLST, there was a higher rate of positive screening tests (35.7 vs. 27.3 %), higher false positive rate (100 vs. 96.4 %), and poor adherence (43 vs. 95 %). Invasive diagnostic follow-up was uncommon and uncomplicated. No interval lung cancer was detected. Late follow-up was mostly attributed to participant or primary care provider preference (67.5 %), participants lost to follow-up (17.5 %), and lack of insurance (10 %).

These findings highlight the potential challenges of generalizing the NLST mortality benefits in the broad deployment of CT screening. Our results support current recommendations that LDCT screening be performed in a highly structured and integrated setting.